1. Field of the Invention
The invention pertains to a piston rod for a vibration damper.
2. Description of the Related Art
U.S. Pat. No. 6,561,326 describes a vibration damper with amplitude-dependent damping force, to the piston rod of which a damping medium-filled chamber is attached, in which a separating piston is installed with freedom to slide back and forth. In FIG. 3 of U.S. Pat. No. 6,561,326, the chamber is formed by a housing, which is connected to the piston rod in the area above a piston. The specification provides no information on the technique used to establish this connection. FIG. 4 discloses a screwed joint between the housing and the piston rod.
A problem is that the screwed joint between the housing and the piston rod should be prevented from getting loosened. A screwed joint is also comparatively expensive.
An object of the present invention is to connect a housing to a piston rod in such a way that the disadvantages of the state of the art are eliminated.